Kentucky Bluegrass
Poa pratensis · Cool-season, Perennial, C3 grass
Grass Family
Poaceae, subfamily Pooideae
Grass Category
Lawn/Turf Grass, Sports Turf
Variety / Cultivar
Standard species type (wild/common type)
Hardiness Zones
USDA Zones 3 to 7, performs exceptionally well in northern climates and northern transition zones.
About This Grass
Forms a rich, dark green to blue-green dense turf with a fine to medium texture. Unmowed height reaches 18-24 inches, typically maintained at 1.5-2.5 inches. Features open, pyramidal panicle seed heads at maturity.
Blade Characteristics
Medium-fine width (2-4mm), flat to folded shape with distinctive boat-shaped tips. Vernation is folded in the bud. Ligule is short and membranous; auricles are absent. Smooth texture with parallel veins.
Root System
Moderate depth fibrous root system combined with aggressive spreading rhizomes. Moderate to high thatch-forming tendency under high fertility and moisture. Slow establishment from seed, but exceptional sod-forming ability and wear recovery.
Growing Information
Origin Region
Europe and Northern Asia; widely naturalized and cultivated across North America and temperate zones
Growth Habit
Rhizomatous, forming a dense, aggressive underground network of creeping stems
Sunlight & Water Needs
Requires full sun (minimum 6-8 hours daily), moderate to high water needs, excellent cold tolerance but moderate drought tolerance (enters summer dormancy under extreme drought). Prefers well-drained, fertile soils with pH 6.0-7.0.
Mowing & Maintenance
Ideal mowing height 1.5 to 2.5 inches. Requires frequent mowing during peak spring/fall growth. High fertilizer requirement (3-5 lbs N per 1000 sq ft/year). Regular aeration and dethatching needed. High maintenance level.
Special Characteristics
Excellent wear tolerance and traffic recovery due to rhizomatous growth. Susceptible to certain diseases like dollar spot, leaf spot, and summer patch. Good cold hardiness and winter color retention compared to warm-season grasses.
Ecological Information
Introduced species in North America. Provides good soil stabilization and erosion control due to dense root and rhizome mat. Serves as a primary lawn turf grass and provides cover for urban wildlife.